The present invention relates to a new and distinct cultivar of self-heal that is grown for use as an ornamental garden plant. The new cultivar is known botanically as Prunella laciniata×grandiflora and will be referred to hereinafter by the cultivar name ‘SUMMER DAZE’.
In 1999 the inventor began a breeding program with the objective of developing new garden cultivars of Prunella species. The program was carried out at a nursery in West Sussex, United Kingdom. The inventor commenced the breeding program by placing a single plant of Prunella laciniata (species, unpatented) as the intended female parent, within a population of plants of Prunella grandiflora (species, unpatented) as potential male parent. The flowers of the Prunelia laciniata plant were found to be fertilized and the inventor was able to collect enough seed to yield 48 first generation seedlings. The inventor observed the growth and flowering of these seedlings for two years, and selected 30 plants with promising characteristics of bright flower color and sturdy plant habit. The inventor set aside these plants in a block and allowed them to be open pollinated. Enough seed was collected to raise 100 plants which were then grown for a further two years in order to identify if any of the plants was worthy of commercial introduction.
In 2004, the inventor selected a single plant, ‘SUMMER DAZE’, for its unique combination of attractive and commercially valuable characteristics including sturdy plant habit, medium-green colored foliage, and long flower heads with clear pink-purple flowers which are borne over a long flowering season.
‘SUMMER DAZE’ differs from the male parent by exhibiting a longer flowering season and increased vigor. ‘SUMMER DAZE’ differs from the female parent by exhibiting leaves which are barely or occasionally lobed, whereas the foliage of the female parent consists of deeply cut lobes. The closest comparison plant known to the inventor is Prunella ‘Bella Deep Rose’ (unpatented). In comparison with ‘Bella Deep Rose’, the flowers of ‘SUMMER DAZE’ are clear pink-purple in color, are borne in longer and larger heads, have a longer flowering season and retain an attractive purple coloration as the flowers age. The flowering duration of Prunella ‘Bella Deep Rose’ is 4 weeks, and its flowers becoming unsightly with age, whereas the flowering duration of ‘SUMMER DAZE’ is in excess of 8 weeks and the flowers remain attractive by developing a purple coloration with age.
‘SUMMER DAZE’ is suitable for planting in garden borders or in containers as single subjects or mixed with other plants. Cultural conditions include full sun to filtered shade, moderate water, and organic loamy soil or substrate. ‘SUMMER DAZE’ reaches 25 cm. in height and 25 cm. in width during the first year, and is hardy to USDA Zone 5.
The first asexual propagation of ‘SUMMER DAZE’ was conducted by the inventor in Binsted Arundel, United Kingdom in 2005 using basal cuttings. The inventor has determined that the distinguishing characteristics of ‘SUMMER DAZE’ have remained stable and uniform, and to be reproduced true to type in subsequent generations of asexual propagation.